1. Field of the Invention
Embodiments of the present invention generally relate to audio driver structures and, more specifically, to methods and systems for managing the power state of an audio device integrated in a graphics device.
2. Description of the Related Art
An increasing number of commercialized computer devices incorporate graphics-dedicated processing systems. In order to increase the processing throughput of the graphics system, multiple graphics processors may be provided in the graphics system. Such a multiprocessor graphics system may utilize a low performance graphics processor that reduces power usage at least in part by reducing graphics data processing performance, and a high performance graphics processor that offers greater graphics processing throughput, but contributes to increased power usage compared with the low power graphics processor. The increased graphics processing throughput may be achieved by operating at a higher clock rate, including two or more graphics processing pipelines, and using wider and/or faster internal and external interfaces. Moreover, to accommodate High-Definition (“HD”) graphics and audio outputs, a HD audio device may also be integrated in the high performance graphics processor. As a result, the higher performance graphics processor is implemented in a larger die size than the lower performance graphics processor in order to include more transistors. Even when a high performance graphics processor is not processing graphics data, it contributes to overall system power consumption due to the static power resulting from transistor leakage. Therefore the static power of the high performance graphics processor is greater than the static power of the low power graphics processor. Consequently, high performance graphics processors are not used in conventional portable systems which are battery powered.
One conventional way to reduce power consumption in a battery powered mode is to turn off the high performance graphics processor. Unfortunately, the shutdown of the high performance graphics processor also removes power from any components related to the high performance graphics processor, such as the HD audio device. While the shutdown of the high performance graphics processor can be controllably performed through graphics drivers, there are no mechanisms in current operating systems to convey this shutdown event to the audio drivers that separately control the HD audio device. As a result, even if the HD audio device has been shut down, the audio drivers may still continue to send streams of audio data to the HD audio device, causing critical system faults.
As the foregoing illustrates, what is needed in the art is thus a system and method that are able to manage the power state of an audio device integrated in a graphics device in an effective manner and address at least the foregoing issues.